skirts the Antilles on their eastern and
northern sides, passes by and among the Bahama Islands, there to
rejoin the part of the stream which entered the Caribbean. This
Caribbean portion of the tide spreads widely in that broad sea, is
constricted again between Cuba and Yucatan, again expands in the Gulf
of Mexico, and is finally poured forth through the Straits of Florida
as a stream having the width of forty or fifty miles, a depth of a
thousand feet or more, and a speed of from three to five miles an
hour, exceeding in its rate of flow the average of the greatest
rivers, and conveying more water than do all the land streams of the
earth. In this part of its course the deep and swift stream from the
Gulf of Mexico, afterward to be named the Gulf Stream, receives the
contribution of slower moving and shallower currents which skirted the
Antilles on their eastern verge. The conjoined waters then move
northward, veering toward the east, at first as a swift river of the
sea having a width of less than a hundred miles and of great depth;
with each step toward the pole this stream widens, diminishing
proportionately in depth; the speed of its current decreases as the
original impetus is lost, and the baffling winds set its surface
waters to and fro in an irregular way. Where it passes Cape Hatteras
it has already lost a large share of its momentum and much of its
heat, and is greatly widened.

Although the current of the Gulf Stream becomes more languid as we go
northward, it for a very long time retains its distinction from the
waters of the sea through which it flows. Sailing eastward from the
mouth of the Chesapeake, the navigator can often observe the moment
when he enters the waters of this current. This is notable not only in
the temperature, but in the hue of the sea. North of that line the
sharpness of the parting wall becomes less distinct, the stream
spreads out broadly over the surface of the Atlantic, yet its
thermometric effects are distinctly traceable to Iceland and Nova
Zembla, and the tropical driftwood which it carries affords the
principal timber supply of the inhabitants of the first-named isle.
Attaining this circumpolar realm, and finally losing the impulse which
bore it on, the water of the Gulf Stream partly returns to the
southward in a relatively slight current which bears the fluid along
the coast of Europe until it re-enters the system of tropical winds
and the currents which they produce. A l